Method of creosoting wood, &amp;c.



UNITED STATES PATENT OFFICE.

CHARLES S. FRIEDMAN, OF PHILADELPHIA, PENNSYLVANIA, ASSIGNOR TO EDGAR A.BANCROFT, TRUSTEE, OF CHICAGO, ILLINOIS.

METHOD OF CR-EOSOTING WOOD, 80C.

SPECIFICATION forming part of Letters Patent No. 693,697, dated February18,1902.

Application filed December 24, 1901.

Serial No. 87,093. (No specimens.)

To all whom it may concern:

Be it known that I, CHARLES S. FRIEDMAN, a citizen of the United States,and a resident of the city of Philadelphia, in the State ofPennsylvania, have invented certain new and useful Improvements inMethods of Oreosoting, of which the followingis a full, clear, and exactdescription.

In creosoting by usual practice the wood or other material undertreatment needs to be thoroughly dried beforehand. Traces of water whichare often detained within the compact cell structure serve to repel theoily creosote and so far defeat its preservative effect, whereas weresaturation complete the inflammable character of the creosote markedlyincreases the risks from destruction by fire. According to the presentinvention the creosote is provided with a suitable vehicle,

such as will enable it to readily permeate the more remote intersticesdespite the presence of water, While the vehicle, owing to its solidnon-combustible character when set, sufiices besides to counteract theevils due to the inflammability of the creosote.

In keeping with the method good results are obtained by use of acompound having ingredients and proportions as follows, viz: glue, onepound; water, two quarts; potash bichromate, (K Gr Q,) three ounces;zinc chlorid, (ZnGl four ounces creosote, two gallons. At the outset theglue is weighed ofi and soaked cold in the requisite amount of water forsome three or four hours until the water is well absorbed, after whichthe temperature is raised to about 150 Fahrenheit, thus melting the glueto the consistency of a thin soup. The zinc chlorid (ZnGl is nextstirred in and dissolved, after which the bichromate of potash (K Or Opreviously prepared as a separate solution at 125 to 150 Fahrenheit(four ounces of water to one ounce of bichromate) is added to completethe creosote .vehicle. This vehicle becomes insoluble andnon-inflammable when its water dries out. A second vessel, fitted with amechanical agitator, contains creosote of, e. g., 1.05 specificgravity,in requisite proportiomheated to about 125 Fahrenheit. Theprepared vehicle is run into this vessel and there thoroughly admixedwith the creosote present,

which latter becomes minutely difiused' through and through the massafter the man- Qncr of an emulsion, owing'to the viscidity of thevehicle. The finished compound passes thence into the ordinarycreosoting-tank and at suitable temperature-e. 9., 150 to 175Fahrenheitis forced into the wood or other material to be impregnated,as in familiar practice.

If preferred, the zinc chlorid (ZnOl separately dissolved in water maybe admixed with the creosote and only the bichromate o'f" In practicepreference is given to creosote of, e. g., 1.05 to 1.10 specificgravity, rich in tar acids and completely liquid at 100 Fahrenheit. Thecreosote should contain at least twenty-five per cent. of constituentsthat do not distilover at 600 Fahrenheit. Thinner creosotes may be used;but they are less efiicacious than the heavier oils.

Obviously the proportions and temperatures heretofore stated are givenonly in way of illustration'and may be varied at suggestion of thoseskilled in the art without essen= tial departure from the invention. Inlieu of zinc chlorid (or zinc sulfate) the corresponding salts of coppercan be taken; but they are more costly. The same objection applies wereefiort made .to replace ordinary glue by other substitutes.

Having thus described my invention, what I claim as new, and desire tosecure by Letters Patent, is

The method of creosotin g wood or other ma.-. terials which consists inemulsifying creosote at proper temperature with a. viscid vehicle havinga glue base and suitable chromium salt to react thereon, and afterthorough admixture to complete the so-called emulsion, forcing the sameinto the interstices of the substance under treatment, substantially asdescribed.

CHARLES S-QFRIEDMAN.

Witnesses: Y i

SIMON J. FRIEDMAN, G. H. BERKHEISER.

